Houston Astros vs Seattle Mariners — Prediction & Odds

September 23, 2026 · Ethan Pecko vs George Kirby · 72°F

2.9% edge · Seattle Mariners

Houston Astros win

43.0%

Seattle Mariners win

57.0%

Fair line (home)

-132

Proj. total

8.58

Score distribution

How often each team scores each run total across all simulations.

Houston Astros (mean 4.07)Seattle Mariners (mean 4.51)

Totals

O/U line

7.5

Proj. total

8.58

Over

54.9%

Under

45.1%

Model vs. market

Side	Model	Book	Fair
Houston Astros	43.0%	+113	+132
Seattle Mariners	57.0%	-123	-132

Projected starters

Starter	IP	K	H	BB	R
Ethan Pecko RHP · Houston Astros	4.3	3.7	4.4	1.9	2.3
George Kirby RHP · Seattle Mariners	5.8	5.1	5.6	1.4	2.4

Strikeout ladder

Ethan Pecko4+ 52%6+ 16%8+ 3%

George Kirby4+ 76%6+ 40%8+ 13%

Per-game averages across all simulations. IP is a decimal average of outs recorded, not baseball's 5.2 notation. R is runs allowed while the starter was still in the game; the simulation models no errors, so every run is earned by construction — which is why this says R and not ER.

Houston Astros — projected lines

Batter	PA	1B	2B	3B	HR	BB	K	AVG	OBP	SLG	OPS
Jose Altuve	4.7	.780	.182	.012	.145	.293	.868	.256	.308	.403	.711
Yordan Alvarez	4.6	.710	.203	.010	.237	.541	.832	.291	.383	.524	.908
Isaac Paredes	4.5	.631	.169	.009	.173	.395	.717	.246	.328	.422	.751
Yainer Diaz	4.4	.771	.187	.009	.159	.132	.752	.266	.294	.427	.721
Christian Walker	4.3	.538	.154	.010	.176	.279	1.098	.223	.283	.400	.684
Taylor Trammell	4.2	.479	.152	.027	.137	.337	1.277	.210	.281	.373	.654
Cam Smith	4.1	.541	.134	.040	.131	.250	1.065	.225	.282	.386	.668
Lucas Spence	3.9	.561	.147	.018	.092	.271	1.092	.226	.288	.353	.640
Nick Allen	3.8	.637	.136	.007	.044	.237	.811	.232	.285	.312	.596

Seattle Mariners — projected lines

Batter	PA	1B	2B	3B	HR	BB	K	AVG	OBP	SLG	OPS
J.P. Crawford	4.6	.670	.156	.004	.111	.634	.856	.240	.353	.367	.720
Randy Arozarena	4.5	.609	.182	.008	.163	.499	1.025	.249	.354	.427	.780
Dominic Canzone	4.4	.642	.170	.018	.202	.388	.942	.260	.331	.465	.795
Cal Raleigh	4.3	.415	.118	.001	.258	.563	1.198	.216	.327	.460	.786
Julio Rodríguez	4.2	.653	.161	.007	.189	.347	.896	.267	.337	.464	.801
Josh Naylor	4.1	.679	.166	.003	.138	.359	.565	.268	.339	.428	.766
Cole Young	4.0	.626	.139	.026	.110	.347	.652	.253	.330	.400	.730
Lazaro Montes	3.8	.396	.115	.011	.209	.390	1.325	.214	.300	.438	.738
Weston Wilson	3.7	.442	.108	.007	.125	.368	1.115	.206	.290	.355	.645

Data notes: away starter Ethan Pecko: only 73 BF vs LHB this season · away starter Ethan Pecko: only 43 BF vs RHB this season · away batter Lucas Spence: only 41 effective PA (3yr weighted) · 19/20 lineup+starter talents from projections